Trunking communication system, trunking server, access network and trunking communication method

ABSTRACT

A trunking communication system, a server, an access network and a trunking communication method are disclosed. The system includes a trunking management server and an access network, the trunking management server includes a trunking call service control module and a connected trunking call media gateway module, where: the trunking call media gateway module is configured to receive service data sent through the access network by a trunking UE, and forward the service data according to a communication type of the service data for implementing user plane communication of the trunking UE; and the trunking call service control module is configured to receive a communication request sent through the access network by a trunking UE, and perform call control and bearer management on the trunking UE according to a communication type of the communication request for implementing control plane communication of the trunking UE.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2012/083521, filed on Oct. 25, 2012, which is hereby incorporatedby reference in its entirety.

TECHNICAL FIELD

Embodiments of the present invention relates to the field ofcommunications technologies, and in particular, to a trunkingcommunication system, a trunking server, an access network and atrunking communication method.

BACKGROUND

Trunking communication is calling between a flock of or a group ofusers, and a conventional trunking communication system cannot satisfydemands of various broadband services, such as a video call, and picturetransmission. With development of an advanced mobile broadbandcommunication system such as a long term evolution (LTE) system, theprior art, such as, the push to talk over cellular (POC) technology,takes the trunking communication as an upper layer application serviceborne by an LTE network, both control plane management and user planedata of the trunking communication are borne at a user plane of an LTEaccess network. When the trunking communication is performed, the LTEnetwork pages terminals in a group one by one, and a downlink service issent to the terminals in the group in a unicast manner.

The trunking communication system is a radio mobile communication systemin which a dynamic channel assignment manner can be implemented toachieve that multiple users share multiple channels, and the system hasfunctions such as scheduling, group calling, preemptive calling, virtualprivate network, and roaming. The trunking communication can be appliedto the field of public security. In a trunking communication group, whena talker user equipment (UE) begins a call, other UEs in the group canhear call content simultaneously.

In the process of research on the prior art, the inventor finds that, inan existing trunking communication process, terminals in a group arepaged in a one-by-one paging manner, so access performance andefficiency are bad; the downlink service is sent in a unicast manner, sooccupancy on downlink channel resources in a system is increased.

SUMMARY

Embodiments of the present invention provide a trunking communicationsystem, a trunking server, an access network and a trunkingcommunication method, so as to solve a problem in the prior art thatneither access performance nor access efficiency of the trunkingcommunication system is high.

In order to solve the foregoing technical problem, the embodiments ofthe present invention disclose the following technical solutions.

In a first aspect, a trunking communication system is provided,including: a trunking management server and an access network, where thetrunking management server includes a trunking call service controlmodule and a connected trunking call media gateway module, the accessnetwork includes a mobile management entity MME, an access networkgateway and a base station eNodeB which communicate with each other, andthe access network gateway includes a multimedia broadcast multicastservice MBMS gateway and a public data network PDN gateway thatcommunicate with the trunking call media gateway module, where thetrunking call media gateway module communicates with the access networkgateway;

the trunking call media gateway module is configured to receive servicedata sent through the access network by a trunking user equipment UEs,and forward the service data according to a communication type of theservice data, so as to implement user plane communication of thetrunking UE; and

the trunking call service control module is configured to receive acommunication request sent through the access network by a trunking UE,and perform call control and bearer management on the trunking UEaccording to a communication type of the communication request, so as toimplement control plane communication of the trunking UE.

In combination with the first aspect, in a first possible implementationmanner, the access network gateway further includes: a serving gatewaycommunicating with the PDN gateway, where each of the serving gatewayand the MBMS gateway communicates with the eNodeB and the MME; and

the access network further includes: a multi-service customer edge MCEcommunicating with the MME and the eNodeB separately; and

In combination with the first possible implementation manner, in asecond possible implementation manner, the trunking call service controlmodule communicates with the MME through an SGt interface, or thetrunking call service control module communicates with the MBMS gatewaythrough an SGmb interface; the trunking call media gateway modulecommunicates with the MBMS gateway through an SGmb-i interface; thetrunking call media gateway module communicates with the PDN gatewaythrough an SGi interface.

In combination with the first possible implementation manner, or thesecond possible implementation manner, in a third possibleimplementation manner,

the PDN gateway, the MBMS gateway and the serving gateway are integratedin one network element; or

the MME and the MCE are integrated in one network element; or

the trunking attribute management module and the trunking call servicecontrol module are integrated in one network element.

In combination with the first possible implementation manner, or thesecond possible implementation manner, or the third possibleimplementation manner, in a fourth possible implementation manner,

the trunking call media gateway module is specifically configured to:when the communication type is point-to-point communication, send, tothe PDN gateway, service data sent by a talker UE among the trunkingUEs, where the PDN gateway forwards, through the serving gateway, theservice data to an eNodeB where a called UE among the trunking UEs islocated, so that the eNodeB sends the service data to the called UE; and

when the communication type is point-to-multipoint communication, send,to the MBMS gateway, service data sent by a talker UE among the trunkingUEs, where the MBMS gateway sends the service data to an eNodeB where amonitoring UE among the trunking UEs is located, so that the eNodeBmulticasts the service data to the monitoring UE.

In combination with the first possible implementation manner, or thesecond possible implementation manner, or the third possibleimplementation manner, or the fourth possible implementation manner, ina fifth possible implementation manner,

the trunking call service control module is specifically configured to:when the communication type is point-to-point communication, send aunicast bearer establishment request or unicast bearer release requestof a trunking UE to the PDN gateway, so that the PDN gateway establishesan EPS bearer for the UE, or releases an established evolved packetsystem EPS bearer; and

when the communication type is point-to-multipoint communication, send atrunking service initiation request of the trunking UE to the MBMSgateway through the trunking call media gateway module, where the MEMSgateway forwards the request to the MCE through the MME, so that the MCEestablishes a downlink multicast bearer for the trunking serviceaccording to the request, and allocates a resource to the trunkingservice.

In combination with the first aspect, or the first possibleimplementation manner, or the second possible implementation manner, orthe third possible implementation manner, or the fourth possibleimplementation manner, or the fifth possible implementation manner, in asixth possible implementation manner, the trunking management serverfurther includes: a trunking information management module and atrunking attribute management module which are connected to the trunkingcall service control module separately;

the trunking information management module is configured to managedefinition, storage and update of trunking UE information and trunkingsubscription information, where the subscription information includes agroup identifier, a group UE list, a trunking UE identity identifier,and a trunking UE priority definition; and

the trunking attribute management module is configured to managedefinition, storage, and update of group attribute information, wherethe attribute information includes a group identifier, a group priority,a group area, and a group service type.

In a second aspect, a trunking management server is provided, and theserver includes: a trunking call service control module and a connectedtrunking call media gateway module, where

the trunking call media gateway module is configured to receive servicedata sent through the access network by a trunking UE, and forward theservice data according to a communication type of the service data, soas to implement user plane communication of the trunking UE; and

the trunking call service control module is configured to receive acommunication request sent through the access network by a trunking UE,and perform call control and bearer management on the trunking UEaccording to a communication type of the communication request, so as toimplement control plane communication of the trunking UE.

In combination with the second aspect, in a first possibleimplementation manner,

the trunking call media gateway module is specifically configured to:when the communication type is point-to-point communication, forwardservice data, sent by a talker UE among the trunking UEs, to a called UEamong the trunking UEs through the access network; and

when the communication type is point-to-multipoint communication,multicast service data, sent by a talker UE among the trunking UEs, to amonitoring UE among the trunking UEs through the access network.

In combination with the second aspect, or the first possibleimplementation manner, in a second possible implementation manner,

the trunking call service control module is specifically configured to:when the communication type is point-to-point communication, send aunicast bearer establishment request or unicast bearer release requestof a trunking UE to the access network, so that the access networkestablishes an EPS bearer for the UE, or releases an established EPSbearer; and

when the communication type is point-to-multipoint communication, send atrunking service initiation request to the access network through thetrunking call media gateway module, so that the access networkestablishes a downlink multicast bearer for the trunking serviceaccording to the request, and allocates a resource to the trunkingservice.

In combination with the second aspect, or the first possibleimplementation manner, or the second possible implementation manner, ina third possible implementation manner, the server further includes: atrunking information management module and a trunking attributemanagement module which are connected to the trunking call servicecontrol module separately, where

the trunking information management module is configured to managedefinition, storage and update of trunking UE information and trunkingsubscription information, where the subscription information includes agroup identifier, a group UE list, a trunking UE identity identifier,and a trunking UE priority definition; and

the trunking attribute management module is configured to managedefinition, storage, and update of group attribute information, wherethe attribute information includes a group identifier, a group priority,a group area, and a group service type.

In a third aspect, an access network is provided, and the access networkincludes: an MME, an access network gateway and an eNodeB whichcommunicate with each other, the access network gateway includes amultimedia broadcast multicast service MBMS gateway and a public datanetwork PDN gateway that communicate with the trunking call mediagateway module, where

the access network gateway is configured to forward service data, sentby a trunking UE, to a trunking management server, so as to implementuser plane communication of the trunking UE; and

the MME is configured to forward a communication request, sent by atrunking UE, to the trunking management server, so as to implementcontrol plane communication of the trunking UE.

In combination with the third aspect, in a first possible implementationmanner, the access network gateway further includes: a serving gatewaycommunicating with the PDN gateway, where each of the serving gatewayand the MBMS gateway communicates with the eNodeB and the MME; and

the access network further includes: an MCE communicating with the MMEand the eNodeB separately; and

In combination with the first possible implementation manner, in asecond possible implementation manner, the PDN gateway is configured to:when user plane communication of the trunking UE is implemented, and acommunication type is point-to-point communication, receive service datasent by a talker UE among the trunking UEs, and send the service data tothe serving gateway; the serving gateway is configured to forward theservice data to an eNodeB where a called UE among the trunking UEs islocated; the eNodeB is configured to send the service data to the calledUE; and

the MBMS gateway is configured to: when user plane communication of thetrunking UE is implemented, and a communication type ispoint-to-multipoint communication, receive service data sent by a talkerUE among the trunking UEs, and send the service data to an eNodeB wherea monitoring UE among the trunking UEs is located; the eNodeB isconfigured to multicast the service data to the monitoring UE.

In combination with the first possible implementation manner, or thesecond possible implementation manner, in a third possibleimplementation manner, the PDN gateway is configured to: when controlplane communication of the trunking UE is implemented, and thecommunication type is point-to-point communication, receive a unicastbearer establishment request or unicast bearer release request sent bythe trunking UE, and establish an EPS bearer for the UE, or release anestablished EPS bearer; and

the MEMS gateway is configured to: when control plane communication ofthe trunking UE is implemented, and the communication type ispoint-to-multipoint communication, receive a trunking service initiationrequest of the trunking UE sent by the trunking management server, andsend the trunking service initiation request to the MME; the MME isconfigured to forward the trunking service initiation request to theMCE; the MCE is configured to establish a downlink multicast bearer fora trunking service of the trunking UE according to the trunking serviceinitiation request, and allocate a resource to the trunking service.

In a fourth aspect, a trunking communication method is provided, and themethod includes:

receiving, by a trunking management server, a group establishmentrequest sent through an access network by a first UE among trunking UEs;

allocating, by the trunking management server, an uplink beareridentifier and a downlink bearer identifier to the trunking UE accordingto the group establishment request; and

establishing, by the trunking management server, an uplink talker bearerand a downlink multicast bearer for the first UE through the accessnetwork according to the uplink bearer identifier and the downlinkbearer identifier respectively, so that a talker UE among the trunkingUEs sends a talker service to a listener UE through the uplink talkerbearer and the downlink multicast bearer.

In combination with the fourth aspect, in a first possibleimplementation manner, the establishing an uplink talker bearer for thetrunking UE through an access network according to the uplink beareridentifier includes:

sending, by the trunking management server, an uplink talker bearerestablishment request message containing an uplink talker beareridentifier to the access network, so that the access network allocatesthe uplink talker bearer identifier to the talker UE among the group UEsaccording to the uplink talker bearer establishment request message,establishes an uplink talker unicast bearer, and establishes a mappingbetween the talker unicast bearer and the uplink talker beareridentifier.

In combination with the fourth aspect, or the first possibleimplementation manner, in a second possible implementation manner, theestablishing a downlink multicast bearer for the trunking UE through anaccess network according to the uplink bearer identifier and thedownlink bearer identifier includes:

sending, by the trunking management server, a group call start requestmessage to the access network, so that the access network allocates adownlink bearer identifier and an Internet protocol IP multicast addressto the group according to the group call start request message, andbinds the IP multicast address and the downlink bearer identifier; and

sending, by the access network, a group session start request message toa base station where the group UE is located, so that the base stationsends a group-based paging notification message to the group UEaccording to the group session start request message; and sending agroup resource scheduling message to the eNodeB where the group UE islocated, so that the eNodeB joins in a multicast group corresponding tothe IP multicast address, and sends a group resource update notificationmessage to the group UE according to the group resource schedulingmessage.

In combination with the fourth aspect, or the first possibleimplementation manner, or the second possible implementation manner, ina third possible implementation manner, the method further includes:

receiving, by the trunking management server, a group end requestmessage sent by the first UE among the trunking UEs;

releasing, by the trunking management server according to the group endrequest message, the uplink bearer identifier and the downlink beareridentifier allocated to the trunking UE; and

sending, by the trunking management server, a group call end requestmessage to the access network, so that the access network releases theuplink talker bearer and the downlink multicast bearer established forthe trunking UE.

In combination with the fourth aspect, or the first possibleimplementation manner, or the second possible implementation manner, orthe third possible implementation manner, in a fourth possibleimplementation manner, the method further includes:

receiving, by the trunking management server, an uplink floorapplication request message sent by the talker UE among the trunkingUEs, and allocating an uplink bearer identifier to the talker UEaccording to the uplink floor application request message;

sending, by the trunking management server, a group status updatemessage to the access network, where the group status update messageincludes a group identifier of the trunking UEs, an identifier of thetalker UE, talker identity information of the talker UE, and a busystatus of the talker UE, so that an eNodeB of the access networkmulticasts the group status update message to the trunking UE; and

sending, by the trunking management server, a talker bearerestablishment request message to the access network, where the talkerbearer establishment request message includes the uplink beareridentifier, the group identifier of the trunking UEs, the identifier ofthe talker UE, and the talker identity information of the talker UE, sothat the access network establishes an EPS bearer for the talker UE.

In combination with the fourth possible implementation manner, in afifth possible implementation manner, the method further includes:

-   -   receiving, by the trunking management server, an uplink floor        release request message sent by the talker UE, and releasing,        according to the uplink floor release request message, the        uplink bearer identifier allocated to the talker UE;

sending, by the trunking management server, a group status updatemessage to the access network, where the group status update messageincludes a group identifier of the trunking UEs, an identifier of thetalker UE, talker identity information of the talker UE, and a freetalker status of the talker UE, so that an eNodeB of the access networkmulticasts the group status update message to the trunking UE; and

sending, by the trunking management server, a talker bearer releaserequest message to the access network, where the talker bearer releaserequest message includes the uplink bearer identifier, the groupidentifier of the trunking UEs, the identifier of the talker UE, and thetalker identity information of the talker UE, so that the access networkreleases the EPS bearer established for the talker UE.

In combination with the fourth aspect, or the first possibleimplementation manner, or the second possible implementation manner, orthe third possible implementation manner, or the fourth possibleimplementation manner, or the fifth possible implementation manner, in asixth possible implementation manner, the method further includes:

receiving, by the trunking management server, a trunking userregistration request message sent through the access network by thetrunking UE, and returning a trunking user registration request responsemessage containing an IP address of the trunking management server tothe access network, so that the access network forwards the trunkinguser registration request response message to the trunking UE; and

receiving, by the trunking management server, a trunking userregistration request message sent by the trunking UE according to the IPaddress of the trunking management server, and returning a trunking userregistration request response message to the trunking UE.

The trunking communication system in the embodiment of the presentinvention includes a trunking management server and an access network,the trunking management server includes a trunking call service controlmodule and a connected trunking call media gateway module, and theaccess network includes an MME, an access network gateway and an eNodeBwhich communicate with each other, where the trunking call media gatewaymodule receives service data sent through the access network by atrunking UE, and forwards the service data according to a communicationtype of the service data, so as to implement user plane communication ofthe trunking UE; and the trunking call service control module receives acommunication request sent through the access network by the trunkingUE, and performs call control and bearer management on the trunking UEaccording to a communication type of the communication request, so as toimplement control plane communication of the trunking UE. In theembodiments of the present invention, user plane communication andcontrol plane communication of the trunking UE can be implementedaccording to different communication types, so the trunking UE can bepaged in a multicast manner in a trunking communication procedure,thereby improving access performance and access efficiency of thesystem. Correspondingly, a downlink service can be sent in a multicastmanner, so occupancy on downlink channel resources in the system is alsoreduced.

BRIEF DESCRIPTION OF THE DRAWINGS

To illustrate the technical solutions in the embodiments of the presentinvention or in the prior art more clearly, the following brieflyintroduces the accompanying drawings required for describing theembodiments or the prior art. Apparently, the accompanying drawings inthe following description show merely some embodiments of the presentinvention, and a person of ordinary skill in the art may still deriveother drawings from these accompanying drawings without creativeefforts.

FIG. 1 is a block diagram of an embodiment of a trunking communicationsystem according to the present invention;

FIG. 2A is a diagram of an implementation solution of a first LTEenhanced eMBMS system architecture according to an embodiment of thepresent invention;

FIG. 2B is a diagram of an implementation solution of a second LTEenhanced eMBMS system architecture to which an embodiment of a trunkingcommunication system of the present invention is applied;

FIG. 2C is a diagram of an implementation solution of a third LTEenhanced eMBMS system architecture to which an embodiment of a trunkingcommunication system of the present invention is applied;

FIG. 2D is a diagram of an implementation solution of a fourth LTEenhanced eMBMS system architecture to which an embodiment of a trunkingcommunication system of the present invention is applied;

FIG. 2E is a diagram of an implementation solution of a fifth LTEenhanced eMBMS system architecture to which an embodiment of a trunkingcommunication system of the present invention is applied;

FIG. 2F is a schematic diagram of a protocol stack in an embodiment ofthe present invention;

FIG. 2G is a schematic diagram of a protocol stack supplementary to FIG.2F;

FIG. 3 is a flow chart of a first embodiment of a trunking communicationmethod according to the present invention;

FIG. 4A-1 and FIG. 4A-2 are a flow chart of a second embodiment of thetrunking communication method according to the present invention;

FIG. 4B is a schematic diagram of launching of an MBMS session in anexisting trunking communication system;

FIG. 4C is a schematic diagram of launching of an MBMS session accordingto an embodiment of the present invention;

FIG. 5 is a flow chart of a third embodiment of a trunking communicationmethod according to the present invention;

FIG. 6 is a flow chart of a fourth embodiment of a trunkingcommunication method according to the present invention;

FIG. 7 is a flow chart of a fifth embodiment of a trunking communicationmethod according to the present invention;

FIG. 8 is a flow chart of a sixth embodiment of a trunking communicationmethod according to the present invention;

FIG. 9 is a flow chart of a seventh embodiment of a trunkingcommunication method according to the present invention;

FIG. 10 is a block diagram of an embodiment of a trunking managementserver according to the present invention;

FIG. 11 is a block diagram of another embodiment of a trunkingmanagement server according to the present invention; and

FIG. 12 is a block diagram of an embodiment of an access networkaccording to the present invention.

DETAILED DESCRIPTION

The following embodiments of the present invention provide a trunkingcommunication system, a trunking server, an access network and atrunking communication method.

To make the technical solutions in the embodiments of the presentinvention more comprehensible for persons skilled in the art, and tomake the aforementioned objectives, characteristics, and advantages ofthe embodiments of the present invention more comprehensible, thetechnical solutions in the embodiments of the present invention arefurther described in detail below with reference to accompanyingdrawings.

FIG. 1 is a block diagram of an embodiment of a trunking communicationsystem according to the present invention.

The trunking communication system includes: a trunking management server110 and an access network 120, the trunking management server 110includes a trunking call service control module 111 and a connectedtrunking call media gateway module 112, and the access network 120includes a mobile management entity MME 121, an access network gateway122 and a base station eNodeB 123 connected to each other. The accessnetwork gateway 122 includes an MBMS gateway 12220 and a PDN gateway12210 that communicate with the trunking call media gateway module 111,the trunking call service control module 111 can directly communicatewith the MME 121, or directly communicate with the access networkgateway 122, and the trunking call service control module 111 can alsocommunicate with the access network gateway 122 through the trunkingcall media gateway module 112. The trunking call media gateway module112 communicates with the access network gateway 122.

The trunking call media gateway module 112 is configured to receiveservice data sent through the access network 120 by a UE among trunkinguser equipments UEs, and forward the service data according to acommunication type of the service data, so as to implement user planecommunication of the trunking UE.

The trunking call service control module ill is configured to receive acommunication request sent through the access network 120 by a UE amongthe trunking UEs, and perform call control and bearer management on thetrunking UE according to a communication type of the communicationrequest, so as to implement control plane communication of the trunkingUE.

The access network gateway 122 may further include: a serving gatewaycommunicating with the PDN gateway 12220, where the serving gateway andthe MEMS gateway 12210 are each connected to the eNodeB 123 and the MME121; the access network 120 may further include: a multi-servicecustomer edge MCE 124 connected to the MME 121 and the eNodeB 123separately. The trunking management server 110 can further include: atrunking information management module and a trunking attributemanagement module which are connected to the trunking call servicecontrol module 111 separately (not shown in FIG. 1).

The trunking call service control module 111 may communicate with theMME 121 through an SGt interface, or the trunking call service controlmodule 111 may communicate with the MBMS gateway 12210 through an SGmbinterface; the trunking call media gateway module 112 may communicatewith the MBMS gateway 12210 through an SGmb-i interface; the trunkingcall media gateway module 112 may communicate with the PDN gateway 12220through an SGi interface.

Optionally, the PDN gateway 12220, the MBMS gateway 12210 and theserving gateway are integrated in one network element; or

the MME 121 and the MCE 124 are integrated in one network element; or

the trunking attribute management module and the trunking call servicecontrol module are integrated in one network element.

Specifically, the trunking call media gateway module 112 may bespecifically configured to: when the communication type ispoint-to-point communication, send, to the PDN gateway 12220, servicedata sent by a talker UE among the trunking UEs, where the PDN gateway12220 forwards, through the serving gateway, the service data to aneNodeB where a called UE among the trunking UEs is located, so that theeNodeB sends the service data to the called UE; and when thecommunication type is point-to-multipoint communication, send, to theMBMS gateway 12210, service data sent by a talker UE among the trunkingUEs, where the MBMS gateway 12210 sends the service data to an eNodeBwhere a monitoring UE among the trunking UEs is located, so that theeNodeB multicasts the service data to the monitoring UE.

Specifically, the trunking call service control module 111 may bespecifically configured to: when the communication type ispoint-to-point communication, send a unicast bearer establishmentrequest or unicast bearer release request of a UE among the trunking UEsto the PDN gateway 12220, so that the PDN gateway 12220 establishes anEPS bearer for the UE, or releases an established evolved packet systemEPS bearer; and when the communication type is point-to-multipointcommunication, send a trunking service initiation request of thetrunking UE to the MEMS gateway 12210 through the trunking call mediagateway module, where the MEMS gateway 12210 forwards the request to theMCE through the MME, so that the MCE establishes a downlink multicastbearer for the trunking service according to the request, and allocatesa resource to the trunking service.

Further, the trunking information management module may be configured tomanage definition, storage and update of trunking UE information andtrunking subscription information, where the subscription informationincludes a group identifier, a group UE list, a trunking UE identityidentifier, and a trunking UE priority definition; the trunkingattribute management module may be configured to manage definition,storage, and update of group attribute information, where the attributeinformation includes a group identifier, a group priority, a group area,and a group service type.

It can be seen from the foregoing embodiment that, in the embodiment,user plane communication and control plane communication of the trunkingUE can be implemented according to different communication types, so thetrunking UE may be paged in a multicast manner in a trunkingcommunication procedure, thereby improving access performance and accessefficiency of the system. Correspondingly, a downlink service can besent in a multicast manner, so occupancy on downlink channel resourcesin the system is also reduced.

Before the embodiment of the present invention is described in detailedbelow, at first, roles in trunking communication involved in theembodiment of the present invention are defined, and these roles mainlyinclude a service UE, a calling service UE, a talker service UE and alistener service UE, where:

the service UE: it refers to any one UE in trunking communication, andif a UE subscribes to an ID of a group in the HLR, the UE becomes aservice UE of the group, and the service UE may have a right forinitiating and receiving a group call;

the calling service UE (briefly referred to as a calling UE or acalling): if a service UE initiates a group call, the service UE is acalling service UE of the current call, and the calling service UE mayend the group call;

the talker service UE (briefly referred to as a talker UE or a talker):talker UE may talk to other UEs in a group, or upload data; beforebecoming a talker, the Service UE needs to first send an application toa trunking management server, and if the trunking management serverallows this request, the service UE becomes a talker; the talker may beconverted into a listener service UE through a release request; and

the listener service UE (briefly referred to as a listener UE or alistener): in a call procedure, except the talker, all service UEsjoining in the group call are listener UEs, and the listener UE may onlylisten to voice or data, and cannot upload voice or data.

Referring to FIG. 2A, it is a schematic diagram of an LTE enhancedmultimedia broadcast and multicast service (eMBMS) system architectureto which an embodiment of a trunking communication system of the presentinvention is applied. The system architecture mainly includes threeparts: a trunking management server, an access network and a UE side.The access network in FIG. 2 may specifically refer to an LTE accessnetwork.

In FIG. 2A, the trunking management server includes: a trunking userinformation and group subscription information management module, atrunking attribute management module, a trunking call service controlmodule and a trunking call media gateway module; the access network mayinclude: a home subscriber server, a mobile management entity (MME), amulti-service customer edge (MCE), an eNodeB, a multimedia broadcastmulticast service (MBMS) gateway, a (PDN) gateway P-GW, a servinggateway S-GW and so on; the UE side mainly includes trunking UEs, andthe trunking UEs include UEs belonging to a same group, and may also bereferred to as group UEs, namely, the trunking and the group refer tothe same meaning. In the embodiment of the present invention, a UE amongthe trunking UEs that obtains a talking right is referred to as a talkerUE.

In different application examples, the trunking user information andgroup subscription information management module and home subscriberserver in the LTE enhanced eMBMS system may be integrated into onenetwork element, as shown in FIG. 2B; the integrated network element maybe named as a home subscriber, trunking user and group subscriptioninformation management module, the module may be connected to thetrunking call service control module through a Cug interface, and beconnected to the MME through an S6a interface separately, the module maybe set in the trunking management server, or may also be set in theaccess network, and configured to share trunking user information andgroup subscription information, and the embodiment of the presentinvention imposes no limitation on this; or, the PDN gateway, the MEMSgateway, and the serving gateway may be integrated into one networkelement, as shown in FIG. 2C; or the MME and the MCE may be integratedinto one network element, as shown in FIG. 2D; or the trunking attributemanagement module and the trunking call service control module may beintegrated into one network element, as shown in FIG. 2E. Furthermore,the trunking attribute management module and the trunking userinformation and group subscription information management module in FIG.2A can be integrated into a module, which is not shown anymore through adrawing here. It should be noted that, in the embodiment of the presentinvention, each module in the trunking management server and eachnetwork element of the access network may be combined flexibly accordingto requirements in an actual application, and the embodiment of thepresent invention imposes no limitation on this.

In the trunking management server:

the trunking user information and group subscription informationmanagement module is configured to manage definition, storage and updateof the trunking user information and the trunking subscriptioninformation, and the managed information includes but is not limited toan identity identifier of a trunking user, priority definition, anidentifier of a subscription group, a group priority, quality of service(QOS) or security information, where an identity identifier of any onetrunking user managed in the trunking user information and groupsubscription information management module is consistent with anidentity identifier of the trunking user saved by the home subscriberserver in the access network, so that the access network can identifythe trunking user according to the identity identifier;

the trunking attribute management module is configured to managedefinition, storage, and update of a group attribute, and the managedinformation includes but is not limited to a group identifier, grouparea definition, a group type, a group service type, QOS or securityinformation;

the trunking call service control module is configured to manage aservice process of a trunking call, where the service process includestrunking call initiation, trunking call end, trunking call uplink talkerfloor management, call forwarding, temporary invitation of memberjoining, and authorized monitoring; and manage a group status and atrunking user status, where the group status may include start, end,talker being free, talker being busy, talker identity and priority, andthe trunking user status includes trunking user registration, trunkinguser deregistration, talking or monitoring, being free or service inprocess; and

the trunking call media gateway module is configured to forward trunkinguser plane data, perform bearer management between the media gatewaymodule and the access network gateway, transparently transmit trunkingapplication layer signaling between the trunking call service controlmodule and the access network gateway, such as, a group call serviceinitiation request, an uplink talker floor application, a group statusupdate, or a security key, and support exchange of trunking service datafrom different networks through protocol stack conversion.

The trunking management server can implement connection with the accessnetwork through an SGt or SGmb interface set on the trunking callservice control module, and an SGi interface and an SGmb-i interface seton the trunking call media gateway module. The SGt interface is acommunication interface between the trunking call service control moduleand the MME of the access network, and is configured to transmit anetwork management message between an application layer of the trunkingmanagement server and the access network, such as, location informationof a UE, status information of a UE in the access network, anddistribution range information of a group call in the access network. Itshould be noted that, the SGt interface is an optional interface, andthe trunking call service control module may also implementcommunication with the access network through the trunking call mediagateway module; the SGmb-i interface is a communication interfacebetween the trunking call media gateway module and the P-GW of theaccess network, and is configured to transmit user plane data or controlplane data of a trunking service; the SGmb-i interface is acommunication interface between the trunking call media gateway moduleand the MBMS gateway of the access network, and is mainly configured totransmit user plane data or control plane data of a point- to-multipointtrunking service.

In the access network:

the MME communicates with the home subscriber server, the MCE, theeNodeB, the MBMS gateway and the serving gateway separately, the MCE,the MBMS gateway and the serving gateway communicate with the eNodeBseparately, and the serving gateway communicates with the PDN gateway,where the eNodeB communicates with an LTE trunking UE of the UE side.The access network in the embodiment of the present invention may beadded with an MCE having a group area management function, and an MBMSgateway supporting a single-cell MBSFN area mode on the basis of anetwork function defined in the existing LTE standard; andsimultaneously added with a group-based paging mechanism, including agroup-based sending function and a group-based receiving function, on anair interface between the eNodeB and the LTE trunking terminal of the UEside; and modify part of MBMS parameters on the M2 interface, the M3interface and the Uu interface, so as to match initiation and end of agroup service, and update of a group area.

The trunking call service control module may communicate with the MMEthrough the SGt interface; the trunking call service control module maycommunicate with the MBMS gateway through the SGmb interface (LTEinterface), or may also directly communicate with the MBMS gateway; thetrunking call service control module may communicate with the PDNgateway through the SGi interface of the trunking call media gatewaymodule, or may also directly communicate with the PDN gateway; thetrunking call media gateway module may communicate with the MBMS gatewaythrough the SGmb-i interface (LTE interface); the trunking call mediagateway module may communicate with the PDN gateway through an SGiinterface.

Based on the access network, the embodiment of the present invention canimplement supporting of group-based paging, and when a group service isinitiated, the access network may notify a trunking user with a group asa unit that the group is to initiate a service, so that after receivingthe notification, the trunking terminal can determine, according tosubscription information of the trunking terminal, whether to receivethe service of the group, and prepare for reception after determiningthat the service of the group is received; the embodiment of the presentinvention can further implement supporting of group-based channelsharing, and in a cell, a downlink monitoring user of a group obtains aservice of the group by sharing a group channel; the embodiment of thepresent invention can further implement group area management,dynamically manage a group area according to a mobile location of atrunking user and an effective area self-defined by a group, anddetermine a corresponding cell-level range for operations such as groupnotification initiation, group notification end, and group resourceallocation.

Based on the LTE enhanced eMBMS system shown in FIG. 2A to FIG. 2E,communication between the trunking management server and a networkelement of the access network includes point-to-point communication andpoint-to-multipoint communication, and different types of communicationare optionally implemented based on the protocol stack listed in theembodiment of the present invention. FIG. 2F is a schematic diagram of aprotocol stack in an embodiment of the present invention.

FIG. 2F includes: a point-to-point protocol stack A, apoint-to-multipoint user plane protocol stack B and apoint-to-multipoint control plane protocol C, where transparenttransmission is corresponding to Relay in English, and an authorization,authentication and accounting protocol is corresponding to Diameter inEnglish.

When the protocol stack in FIG. 2F is applied for implementing userplane communication, for the point-to-point communication and thepoint-to-multipoint communication, service data transmitted by a talkerUE is sent to the trunking call media gateway module based on theprotocol stack A. When the trunking call media gateway module forwardsdata according to a communication type, if the communication type ispoint-to-point communication, the trunking call media gateway modulesends the service data of the talker UE to the PDN gateway through, forexample, the SGi interface, and then the service data is sent to acalled UE based on the protocol stack A; if the communication type ispoint-to-multipoint communication, the trunking call media gatewaymodule sends the service data of the talker UE to the MBMS gatewaythrough, for example, the SGmb-i interface, then the MBMS gatewayforwards, based on the protocol stack B, the service data through the M1interface to a relevant eNodeB of a group where the talker UE islocated, and the eNodeB multicasts, through the Uu interface, theservice data to all monitoring UEs in the group.

When the protocol stack in FIG. 2F is applied for implementing controlplane communication, no matter whether it is point-to-pointcommunication or point-to-multipoint communication, a call initiationrequest, an end request, a talker floor application request, or a talkerfloor release request is sent by a corresponding UE in a group to thetrunking call service control module based on the protocol stack A. Thetrunking call service control module performs call control and bearermanagement according to the communication type, and if the communicationtype is point-to-point communication, the trunking call service controlmodule sends, through, for example, the SGi interface, a unicast bearerestablishment request or unicast bearer release request of a calling UEor called UE to the access network which can be the PDN gateway, andthen the PDN gateway establishes an evolved packet system (EvolvedPacket System, EPS) bearer satisfying QOS of the calling UE, or releasesan EPS bearer corresponding to the called UE. The trunking call servicecontrol module performs call control and bearer management according tothe communication type, and if the communication type ispoint-to-multipoint communication, the trunking call service controlmodule sends, through an interface such as the SGmb interface, a groupservice initiation request or group service end request to the MBMSgateway based on the protocol stack C, the MEMS gateway sends a controlmessage to the MME through, for example, the Sm interface, the MMEforwards the control message to the MCE through the M3 interface, theMCE establishes a downlink multicast bearer according to the controlmessage, and allocates a resource to the group service, and meanwhileforwards it to the eNodeB through the M2 interface, and the eNodeBmulticasts the downlink multicast bearer established for the groupservice and the resource allocated to the group service to all the UEsin the group through the Uu interface; or, the group service callcontrol module initiates a unicast call establishment request to thecalled UE, the called UE initiates a unicast bearer establishmentrequest to an EPC, the EPC replies the UE with a response after theestablishment is completed, and the UE returns unicast called bearerestablishment completion to a PTT Server after receiving the response.

Further, in the system architecture shown in FIG. 2A to FIG. 2E, for thesystem architecture in which the trunking user information and groupsubscription information management module, and the home subscriberserver are individually set, the Chh interface may be further set toconnect the trunking user information and group subscription informationmanagement module, and the home subscriber server. When the trunkinguser information and group subscription information management module,and the home subscriber server are connected for the first time, orafter updating trunking user information and group subscriptioninformation, the trunking user and group subscription informationmanagement module notifies the home subscriber server that the homesubscriber server can obtain a mapping between a group identifier in thetrunking user information and group subscription information managementmodule and a corresponding trunking user identity identifier through theChh interface, so that the home subscriber server internally establishesa mapping between a group identifier and a group user identifier (suchas, an IMIS), or an IP of a group user in the access network, whereupdate of the trunking user information and the group subscriptioninformation includes but is not limited to addition or deletion of agroup member in an existing group, and new addition of a group and agroup member thereof. Correspondingly, after obtaining group IDinformation from the Sm interface or the SGt interface, the MME may alsoobtain information such as a UE ID (such as, an IMIS) or a UE IPcorresponding to a group user from the home subscriber server. Bysetting the Chh interface between the trunking user information andgroup subscription information management module, and the homesubscriber server, signaling interaction of the control plane can bereduced, thereby reducing group establishment latency and groupcommunication user plane latency.

Referring to FIG. 2G, it is a schematic diagram of a protocol stacksupplementary to FIG. 2F, which includes a protocol stack between thehome subscriber server and the trunking user and group subscriptioninformation management module, and a protocol stack between the homesubscriber server, the trunking user and group subscription informationmanagement module and the trunking call service control module.

Referring to FIG. 3, it is a flow chart of an embodiment of a trunkingcommunication method of the present invention, and the trunkingcommunication method can be applied to the trunking communication systemin FIG. 1.

Step 301: A trunking management server receives a group establishmentrequest sent through an access network by a first UE among trunking UEs.

The first UE in this embodiment is the calling service UE defined above.

Step 302: The trunking management server allocates an uplink beareridentifier and a downlink bearer identifier to the trunking UE accordingto the group establishment request.

Step 303: The trunking management server establishes an uplink talkerbearer and a downlink multicast bearer for the trunking UE through theaccess network according to the uplink bearer identifier and thedownlink bearer identifier respectively, so that a talker UE among thetrunking UEs sends a talker service to a listener UE through the uplinktalker bearer and the downlink multicast bearer.

Specifically, the trunking management server sends an uplink talkerbearer establishment request message containing an uplink beareridentifier to the access network, so that the access network allocatesthe uplink talker bearer identifier to the talker UE among the group UEsaccording to the uplink talker bearer establishment request message,establishes an uplink talker unicast bearer, and establishes a mappingbetween the talker unicast bearer and the uplink talker beareridentifier.

Specifically, the trunking management server sends a group call startrequest message to the access network, so that the access networkallocates a downlink bearer identifier and an Internet protocol IPmulticast address to the group according to the group call start requestmessage, and binds the IP multicast address and the downlink beareridentifier; and the access network sends a group session start requestmessage to a base station where the group UE is located, so that thebase station sends a group-based paging notification message to all UEsof the group according to the group session start request message; andsends a group resource scheduling message to an eNodeB where the groupUE is located, so that the eNodeB joins in a multicast groupcorresponding to the IP multicast address, and sends a group resourceupdate notification message to the group UE according to the groupresource scheduling message.

Further, the method may further include: receiving, by the trunkingmanagement server, a group end request message sent by the first UEamong the trunking UEs; releasing, by the trunking management serveraccording to the group end request message, the uplink bearer identifierand the downlink bearer identifier allocated to the trunking UE; andsending, by the trunking management server, a group call end requestmessage to the access network, so that the access network releases theuplink talker bearer and the downlink multicast bearer established forthe trunking UE.

Further, the method may further include: receiving, by the trunkingmanagement server, an uplink floor application request message sent by atalker UE among the trunking UEs, and allocating an uplink beareridentifier to the talker UE according to the uplink floor applicationrequest message; sending, by the trunking management server, a groupstatus update message to the access network, where the group statusupdate message includes a group identifier of the trunking UEs, anidentifier of the talker UE, talker identity information of the talkerUE, and a busy status of the talker UE, so that an eNodeB of the accessnetwork multicasts the group status update message to the trunking UE;and sending, by the trunking management server, a talker bearerestablishment request message to the access network, where the talkerbearer establishment request message includes the uplink beareridentifier, the group identifier of the trunking UEs, the identifier ofthe talker UE, and the talker identity information of the talker UE, sothat the access network establishes an EPS bearer for the talker UE.

Further, the method may further include: receiving, by the trunkingmanagement server, an uplink floor release request message sent by thetalker UE, and releasing, according to the uplink floor release requestmessage, the uplink bearer identifier allocated to the talker UE;sending, by the trunking management server, a group status updatemessage to the access network, where the group status update messageincludes a group identifier of the trunking UEs, an identifier of thetalker UE, talker identity information of the talker UE, and a freetalker status of the talker UE, so that an eNodeB of the access networkmulticasts the group status update message to the trunking UE; andsending, by the trunking management server, a talker bearer releaserequest message to the access network, where the talker bearer releaserequest message includes the uplink bearer identifier, the groupidentifier of the trunking UEs, the identifier of the talker UE, and thetalker identity information of the talker UE, so that the access networkreleases the EPS bearer established for the talker UE.

Further, the method may further include: receiving, by the trunkingmanagement server, a trunking user registration request message sentthrough the access network by the trunking UE, and returning a trunkinguser registration request response message containing an IP address ofthe trunking management server to the access network, so that the accessnetwork forwards the trunking user registration request response messageto the trunking UE.

Further, the method may further include: receiving, by the trunkingmanagement server, a trunking user registration request message sent bythe trunking UE according to the IP address of the trunking managementserver, or receiving, by the trunking management server, a trunking userregistration request message sent by the trunking UE according to theidentifier of the trunking management server, and returning a trunkinguser registration request response message to the trunking UE.

It can be seen from the foregoing embodiment that, in this embodiment,user plane communication and control plane communication of the trunkingUE may be implemented according to different communication types, so thetrunking UE can be paged in a multicast manner in a trunkingcommunication procedure, thereby improving access performance and accessefficiency of the system. Correspondingly, a downlink service can besent in a multicast manner, so occupancy on downlink channel resourcesin the system is also reduced.

An embodiment of the trunking communication method of the presentinvention is described in detail below in combination with the systemarchitecture and the protocol stack shown in FIG. 2A to FIG. 2F.

Referring to FIG. 4A-1 and FIG. 4A-2, they are a flow chart of a secondembodiment of a trunking communication method of the present invention,and this embodiment describes a group establishment procedure duringtrunking communication, where a trunking calling UE may be any one UE ina group.

Step 400: A trunking UE in a group enters a radio resource control(Radio Resource Control, RRC) connection status, establishes an evolvedpacket system (Evolved Packet System, EPS) bearer between the trunkingUE and a PDN gateway, and meanwhile enables a protocol stack A.

Step 401: A trunking calling UE sends, based on a protocol stack A, agroup establishment request message based on an application layer to atrunking call service control module, where the group establishmentrequest message can include a group identifier, a calling identity, agroup call type, and a service identifier.

Step 402: The trunking call service control module sends a group bearerestablishment request message to a trunking call media gateway module,where the group bearer establishment request message is used to requestallocating a corresponding uplink bearer identifier and a correspondingdownlink bearer identifier to the group.

Step 403: The trunking call media gateway module allocates resourcessuch as the uplink bearer identifier and the downlink bearer identifierto the group.

Step 404: The trunking call media gateway module sends a group bearerestablishment request response message to the trunking call servicecontrol module, where the group bearer establishment request responsemessage carries the uplink bearer identifier and the downlink beareridentifier which are allocated. The uplink bearer identifier and thedownlink bearer identifier are used to identify, when the trunking callmedia gateway module subsequently exchanges user plane data with the PDNgateway and the MBMS gateway, a group to which the exchanged databelongs. For example, if the uplink bearer identifier allocated by thetrunking call media gateway module to the group 1 is 10, and thedownlink bearer identifier allocated by the trunking call media gatewaymodule to the group 1 is 20, the trunking call media gateway moduleexchanges data on the uplink bearer with the identifier being 10 to thedownlink bearer with the identifier being 20, thereby implementing thatdata sent by the talker UE in the group 1 on the uplink bearer 10 can beforwarded to other UEs in the group 1 through the downlink bearer 20.

Step 405: The trunking call service control module confirms, by queryinga trunking attribute management module, whether the group establishmentrequest message is valid, and sends, when being valid, a groupestablishment request response message based on an application layer tothe trunking UE, where the group establishment request response messagecan include information such as a group identifier, a group member list,a group call type, and a service identifier, so as to denote that themessage is already handled. In addition, if the group establishmentrequest message is invalid, the trunking call service control module maynot respond to the group establishment request message, and stop asubsequent operation.

Step 406 to step 418: Establish a downlink multicast bearer for a UE inthe group.

Step 406: The trunking call service control module sends a group callstart request message to the MEMS gateway through the SGmb-i interfaceof the trunking call media gateway module, where the group call startrequest message carries the downlink bearer identifier allocated by thetrunking call media gateway module to the group, and a parameter such asa group identifier, and QOS.

Step 407: The MBMS gateway allocates an IP multicast address to thegroup, and maps the IP multicast address and the downlink beareridentifier of the group on the SGmb-i interface, so that subsequentlythe trunking call media gateway module may transmit a downlink groupservice to a cell corresponding to the IP multicast address according tothe mapping.

Step 408: The MBMS gateway sends a group session start request message(serving as an MBMS Service Session) to the MME through the Sminterface, where the group session start request message may carryinformation such as a group identifier (which can be, for example, aTMGI), a group member list, group area definition, and QOS.

Step 409: The MME sends an MBMS session start request message to an MCEthrough the M3 interface according to the group session start requestmessage, where the MBMS session start request message may carryinformation such as a group identifier, an initial area of group serviceinitiation, and QOS.

Step 410: The MCE forwards an MEMS session start request message to aneNodeB through the M2 interface.

Step 411: The eNodeB that receives the MBMS session start requestmessage sends a group-based paging notification message to a UE of thegroup through the Uu interface, so that the UE in the group prepares toreceive group service data after receiving the group-based pagingnotification message, including establishment of a bearer link andinitialization of an application layer configuration with an accessnetwork.

Step 412: The eNodeB that receives the MBMS session start requestmessage sends an MBMS session start request response message to the MCEthrough the M2 interface.

Step 413: The MCE sends an MEMS gateway resource scheduling message tothe eNodeB through the M2 interface according to the initial area wherethe group service is initiated, and allocates a corresponding radioresource to the group downlink service.

Step 414: The eNodeB that receives the MBMS gateway resource schedulingmessage updates an MBMS resource indication channel on an air interfaceaccording to the resource scheduling message, and sends a group resourceupdate notification message to the UE in the group, where the groupresource update notification message includes resource information of agroup downlink traffic channel.

Step 415: The eNodeB that receives the MBMS gateway resource schedulingmessage sends an MBMS gateway resource scheduling response message tothe MCE through the M2 interface.

Step 415 a: In synchronization with step 315, the eNodeB that receivesthe MBMS gateway resource scheduling message joins in the IP multicastaddress of the group.

Step 416: After receiving the MBMS gateway resource scheduling responsemessage, the MCE sends an MBMS session start request response message tothe MME through the M3 interface.

Step 417: The MME sends a group session start request response messageto the MBMS gateway.

Step 418: The MBMS gateway sends a group session start request responsemessage to the trunking call service control module.

Step 419 to step 422: Establish an uplink bearer for a talker UE in thegroup, and the step 419 to step 422 may be executed in synchronizationwith the foregoing step 406 to step 418.

Step 419: The trunking call service control module sends an uplinktalker bearer establishment request message to the access network, suchas a PDW gateway through the SGi interface of the trunking call mediagateway module, where the message carries an uplink talker UE beareridentifier, a group identifier, a talker UE identifier, and a QOSparameter allocated by the trunking call media gateway module to thetalker UE in the group.

Step 420: The access network, such as a PDW gateway, establishes anuplink talker unicast bearer for the talker UE in the group according tothe uplink talker bearer establishment request message, where the uplinktalker unicast bearer is a unicast bearer capable of satisfying aservice QOS requirement of the talker UE.

In this embodiment, the uplink talker UE may be the calling UE in step401.

Step 421: The PDN gateway establishes a mapping between the uplinktalker unicast bearer and a talker bearer identifier of the group on theSGi interface.

Step 422: The PDW gateway sends an uplink talker bearer establishmentrequest response message to the trunking call service control module.

Step 423: After the LTE access network completes establishment of theuplink bearer and the downlink bearer of the group, the trunking callservice control module can send a talker floor grant message based onthe protocol stack A or based on the point-to-multipoint protocol stackB through the SGi interface, such as, send the talker floor grantmessage to a calling UE in the group, and the UE receiving the talkerfloor grant message may start sending talker service data as the talkerUE in the group.

Delivery of the talker floor grant message is one of necessaryconditions for successfully initiating a group service. For example, thecalling UE as a talker UE may start an applied group service, such as avoice call after receiving the talker floor grant message. At this time,for uplink unicast communication, group service data of the talker UE issent to the trunking call media gateway module according to the protocolstack A; for downlink multicast communication, the trunking call mediagateway module sends the multicast data to the MBMS gateway through theSGmb-i interface, the MBMS-GW sends, according to the protocol stack B,the multicast data to an eNodeB where other UEs in the group arelocated, and the eNodeB sends the multicast data to other UEs of thegroup in a channel shared manner according to an LTE eMBMS mechanism onan air interface; generally a service of a group can be regarded as anMBMS session.

Step 424: The trunking call service control module sends a group statusupdate notification message based on an application layer to the MBMSgateway, where the group status update notification message includes anidentifier of a talker UE, and a priority of a talker UE.

Step 425: The MBMS gateway sends the group status update notificationmessage to the eNodeB through the M1 interface.

Step 426: The eNodeB forwards the group status update notificationmessage to other UEs in the trunking.

It should be noted that, in the embodiment shown in FIG. 4A-1 and FIG.4A-2, step 419 and step 403 can be executed in parallel, and step 423and step 403 can also be executed in parallel; step 423 can be directlyexecuted after step 418; step 418 can be executed in advance after step406; step 406 and step 419 can be executed in parallel, and the flowchart shown in FIG. 4A-1 and FIG. 4A-2 imposes no limitation on this.

Furthermore, at the same time of initiating step 401, the UE can alsoinitiate talker bearer establishment to the PDN gateway of the accessnetwork, so as to replace step 419 to step 422 (a dedicated bearerestablished from the UE side). Specifically, step 420 in FIG. 4A-1 andFIG. 4A-2 may be first executed, and the name of the transmitted messageis modified into the UE initiation uplink talker bearer establishmentand bearer establishment completion message; then step 419 is executed,and the name of the transmitted message is modified into the talkerbearer identifier and uplink talker bearer mapping request message;finally, step 422 is executed, the name of the transmitted message ismodified into the talker bearer identifier and uplink talker bearermapping response message.

Furthermore, different from that in FIG. 4A-1 and FIG. 4A-2, thetrunking management server initiates uplink bearer establishment (step419 to step 422), in an optional embodiment, the trunking UE mayinitiate, at the same time of executing step 401: sending a groupestablishment request, an uplink talker bearer establishment request tothe access network, and completes uplink talker bearer establishment ofthe trunking UE through interaction with the eNB, the MME and the PDNgateway of the access network.

In this embodiment, when a group downlink service is implemented, agroup service may be regarded as an MBMS session based on an existingLTE MBMS mechanism, and the LTE access network allocates a correspondingtemporary mobile group identity (TMGI) and a corresponding logic channelidentifier to the MBMS Session. Generally a launch area of a groupservice is usually decided by the actual location of the group UE,namely, a set of cells where UEs of the group are located forms thelaunch area of the group service; or, a valid area of the group may alsobe predefined, and the valid area is used as a group attribute.

A schematic diagram of launch of an existing MBMS session is shown inFIG. 4B, and a group service launch area may be formed of several MBSFNareas, where services of the same group may be mapped into differentMBMS over the single frequency network (MBSFN) areas (areas); in thesame MBSFN area, services of the same group are regarded as an MBMSSession, which is borne on an MBMS point-to-multipoint traffic channel(MTCH) in the MBSFN area, and each MTCH bears services from the samegroup. In FIG. 4B, a part of the MBSFN area1, and apart of the MBSFNarea2 fall out of the launch area required for a group service, andaccording to the existing LTE eMBMS mechanism, actually services of thegroup are also launched on these areas, so network resources are wasted.

In the embodiment of the present invention, the foregoing defect can beovercome in a manner of shrinking the MBSFN area. FIG. 4C is a schematicdiagram of launching of an MBMS session in an embodiment of the presentinvention. One launch manner can be: only one cell exists in each MBSFNarea, and the MBSFN sub-frame design in the original MBSFN areamulti-cell mode is still reused, namely, the long cyclic prefix CP, theMBSFN pilot, and the MBSFN area-specific scrambling are still used in anMBSFN sub-frame; the other launch manner can be: only one cell exists ineach MBSFN area; at this time, the CP length and the CRS pilot(including the format of CRS pilot signal generation and CRS pilotdistribution, and the number of CRS pilots) adopted by the cellnon-MBSFN sub-frame are adopted in an MBSFN sub-frame, and thesingle-antenna port (single-antenna port) or transmit diversity mode issupported according to the number of CRS pilots.

For the MBMS Session single-cell mode shown in FIG. 4C, an identifier(such as, 1 bit) can be added into a system information block (SIB) 13,so as to indicate whether a given MBSFN area is in an MBMS multi-cellmode or in a single-cell mode.

Referring to FIG. 5, it is a flow chart of a third embodiment of atrunking communication method according to the present invention, andthis embodiment describes a group end procedure during trunkingcommunication.

Step 500: A calling UE in a group enters an RRC connection status,establishes an EPS bearer between the calling UE and a P-GW, andmeanwhile enables a protocol stack A.

Step 501: The calling UE sends a group end request message to a trunkingcall service control module based on the protocol stack A, where thegroup end request message includes a group identifier, and a serviceidentifier.

Step 502: The trunking call service control module confirms whether thegroup end request message is valid, and if valid, sends a group endrequest response message to the calling UE, where the group end requestresponse message includes information such as a group identifier, agroup call type, and a service identifier, denoting that the message isalready handled; or otherwise, does not respond to the group end requestresponse message, and stops a subsequent operation.

Step 503: The trunking call service control module sends a group bearerrelease request message to a trunking call media gateway module, wherethe group bearer establishment request message is used to requestreleasing an uplink bearer identifier and a downlink bearer identifierallocated to the group.

Step 504: The trunking call media gateway module sends a group bearerrelease request response message to the trunking call service controlmodule.

Step 505 to step 513: Release a downlink multicast bearer for a UE inthe group.

Step 505: The trunking call service control module sends a group callend request message to an MBMS gateway through an SGmb interface.

Step 506: The MEMS gateway forwards a group call end request message toan MME.

Step 507: The MME sends an MEMS session end request message to the MCEthrough an M3 interface.

Step 508: The MCE forwards the MEMS session end request message to aneNodeB through an M2 interface.

Step 509 a: The eNodeB releases a group resource according to the MEMSsession end request message.

Step 509 b: The eNodeB sends a group resource update notificationmessage to the UE in the group.

Step 509 c: The eNodeB exits the multicast IP address of the group.

Step 510: The eNodeB returns an MBMS session end request responsemessage to the MCE through the M2 interface.

Step 511: The MCE forwards the MBMS session end request response messageto the MME through the M3 interface.

Step 512: The MME returns a group call end request response message tothe MBMS gateway.

Step 513: The MBMS gateway forwards the group call end request responsemessage to the trunking call service control module.

Step 514: The trunking call service control module sends an uplinktalker bearer release request message to the PDW gateway through an SGiinterface.

Step 515: The PDN gateway releases, according to the uplink talkerbearer release request message, an uplink talker unicast bearerestablished for the talker UE in the group.

Step 516: The PDW gateway returns an uplink talker bearer releaserequest response message to the trunking call service control module.

FIG. 6 is a flow chart of a fourth embodiment of a trunkingcommunication method according to the present invention, and thisembodiment describes a procedure that a trunking UE in a group appliesfor an uplink talker floor after the group is established duringtrunking communication.

Step 600: By sending a group status indication message to the trunkingUE, an eNodeB notifies a trunking UE that the trunking UE is currentlyin an uplink free status.

Step 601: The trunking UE sends an uplink floor application requestmessage based on an application layer to a trunking call service controlmodule based on the protocol stack A, where the uplink floor applicationrequest message includes a group identifier, identity information (suchas, a UE identifier) of the trunking UE as a calling UE, a group calltype, and a service identifier.

Step 602: The trunking call service control module confirms, by queryinga trunking user information and group subscription informationmanagement module, whether the uplink floor application request messageis valid, and if valid, sends a group talker bearer establishmentrequest message to a trunking call media gateway module, where the grouptalker bearer establishment request message is used to requestallocating a corresponding uplink bearer identifier to a talker UE.

Step 603: The trunking call media gateway module returns a group talkerbearer establishment response message to the trunking call servicecontrol module, where the group talker bearer establishment responsemessage contains the uplink bearer identifier allocated to the groupduring group establishment.

Step 604: The trunking call service control module sends a group statusupdate message to the trunking call media gateway module, where thegroup status update message contains a group identifier, a busy talkerstatus, talker identity information, and a talker priority.

Step 604 a: The trunking call media gateway module transparentlytransmits the group status update message to an MBMS gateway.

Step 604 b: The MBMS gateway transparently transmits the group statusupdate message to the eNodeB.

Step 604 c: The eNodeB multicasts the group status update message to aUE in the group, so that the UE in the group stops application for thetalker floor after receiving the message when the priority of a UE isnot higher than the priority of the trunking UE with the currentapplication talker floor.

Step 605: The trunking call service control module sends a talker bearerestablishment request message to a PDN gateway, where the talker bearerestablishment request message contains an uplink bearer identifier, agroup identifier, a talker identifier, and a QOS parameter.

Step 606: The PDN gateway forwards a talker bearer establishment requestmessage to an MME.

Step 606 a: The MME establishes an EPS bearer for a trunking UE as atalker UE.

Step 607: The MME returns a talker bearer establishment completionmessage to the PDN gateway, so that the PDN gateway completes themapping between the talker bearer trunking and the EPS bearer.

Step 608: The PDN gateway sends the talker bearer establishmentcompletion message to the trunking call service control module.

Step 609: The trunking call service control module sends a talker floorauthorized message to the talker UE in the group based on the protocolstack A through the SGi interface, so that talker UE initiates a talkerservice after receiving the message.

It should be noted that, the step 602 and step 605 may be executed inparallel; at the same time of executing step 601, the UE may initiatetalker bearer establishment to the PDN gateway of the access network, soas to replace step 606 to step 607 (a dedicated bearer established fromthe UE side). Specifically, step 606 a in FIG. 6 may be first executed,and the name of the message is modified into the uplink talker bearerestablishment and bearer establishment completion message; then step 606is executed, and the name of the message is modified into the talkerbearer identifier and uplink talker bearer mapping request message;finally, step 608 is executed, the name of the message is modified intothe talker bearer identifier and uplink talker bearer mapping responsemessage. Furthermore, the “group status update” in FIG. 6 may beexecuted after the “establish an access network bearer for a talker”; atthis time, step 609 is an optional step, and meanwhile step 607 can bedeleted.

Furthermore, different from that in FIG. 6, the trunking managementserver initiates establishment of an uplink EPS bearer for a talker(step 419 to step 422), in an optional embodiment, at the same time ofexecuting step 601: send an uplink floor application request, thetrunking UE may initiate a talker EPS bearer establishment request tothe access network, and establish an uplink EPS bearer for the talker UEthrough interaction with the eNB, the MME, the PDN gateway and theserving gateway of the access network.

The process shown in FIG. 6 may be processed in parallel with theforegoing process shown in FIG. 4A-1 and FIG. 4A-2.

Referring to FIG. 7, it is a flow chart of a fifth embodiment of atrunking communication method according to the present invention, andthis embodiment describes an uplink talker floor release procedureduring trunking communication.

Step 701: A talker UE sends an uplink floor release request message to atrunking call service control module based on a protocol stack A, wherethe uplink floor release request message includes a group identifier, acalling identity, a group call type, and a service identifier.

Step 702: The trunking call service control module sends a group talkerbearer release request message to a trunking call media gateway module,where the group bearer establishment request message is used to requestreleasing an uplink bearer identifier allocated to a talker.

Step 703: The trunking call media gateway module sends a group talkerbearer release response message to the trunking call service controlmodule.

Step 704: The trunking call service control module sends a group statusupdate message to the trunking call media gateway module, where themessage includes a group identifier, an talker status, talker identityinformation, and a talker priority.

Step 704 a: The trunking call media gateway module transparentlytransmits the group status update message to an MBMS gateway.

Step 704 b: The MBMS gateway transparently transmits the group statusupdate message to the eNodeB.

Step 704 c: The eNodeB multicasts the group status update message to theUE in the group.

Step 705: The trunking call service control module sends a group talkerbearer release request message to a PDN gateway.

Step 706: The PDN gateway forwards the group talker bearer releaserequest message to an MME.

Step 706 a: The MME releases an EPS bearer established for the talkerUE.

Step 707: The MME returns a talker bearer release completion message tothe PDN gateway, so that the PDN gateway deletes a mapping between atalker bearer trunking and the EPS bearer.

Step 708: The PDN gateway forwards the talker bearer release completionmessage to the trunking call service control module.

Referring to FIG. 8, it is a flow chart of a sixth embodiment of atrunking communication method according to the present invention, thisembodiment describes a registration procedure of a trunking UE at thetime of implementing trunking communication, and the trunking UE in thisembodiment does not know an IP address of the trunking call servicecontrol module in advance.

Step 801: A trunking UE sends, after being switched on, an attachrequest (Attach Request) message to an MME, where the attach requestmessage contains a UE trunking capability identifier and securityinformation.

Step 802: Complete an authentication and security process(Authentication/Security) in an LTE network between the trunking UE, theMME and a home subscriber server.

Step 803: The MME sends, after identifying the trunking UE according tothe UE trunking capability identifier, a trunking user registrationrequest message to the trunking call service control module, where thetrunking user registration request message contains an identityidentifier for uniquely identifying a trunking UE, such as, aninternational mobile subscriber identity (International MobileSubscriber Identity, IMSI).

Step 804: Perform group authentication and security authentication(Authentication/Security) between the trunking UE, the trunking callservice control module, and a trunking user information and groupsubscription information management module.

Step 805: The trunking call service control module sends a trunking userregistration request response message to the MME, where the trunkinguser registration request response message includes the IP address ofthe trunking call service control module.

Step 805 a: The MME forwards the trunking user registration requestresponse message to the trunking UE.

Referring to FIG. 9, it is a flow chart of a seventh embodiment of atrunking communication method according to the present invention, thisembodiment describes another registration procedure of a trunkingterminal during trunking communication, and the trunking UE in thisembodiment knows an IP address of the trunking call service controlmodule in advance.

Step 901: A trunking UE sends, after being switched on, an attachrequest (Attach Request) message to an MME, where the attach requestmessage contains a UE trunking capability identifier and securityinformation.

Step 902: Complete an authentication and security process(Authentication/Security) in an LTE network between the trunking UE, theMME and a home subscriber server.

Step 902 a: The MME returns an attach request response message to thetrunking UE.

Step 903: The trunking UE sends a trunking user registration requestmessage to the trunking call service control module.

Step 904: Perform group authentication and security authentication(Authentication/Security) between the trunking UE, the trunking callservice control module, and a trunking user information and groupsubscription information management module.

Step 905: The trunking call service control module returns a trunkinguser registration request response message to the trunking UE, where thetrunking user registration request response message may include the IPaddress of the trunking call service control module.

In the foregoing group communication embodiment, the trunking callcontrol module is mainly responsible for group status management, andthe following may be implemented through status management: in oneaspect, status information of current trunking service running isprovided to the trunking UE for convenience of scheduling or statistics;in the other aspect, the current group status information may bepublished to the access network, for example, the group UE applies forthe talker floor at appropriate time according to group talker statusinformation.

A group status management function is classified into user-level statusmanagement (user-level), and group-level status management group-level,and the following Table 1 is an example of a kind of group statusmanagement function:

TABLE 1 Status management function name Description AttributeRegistration/deregistration If a user registers user-levelattached/detached successfully in a trunking management module, the useris in a registered status; otherwise the user is in a deregistrationstatus Point call being busy/free If a user is performing a user-leveldedicated (busy/free) point call service (talking/receiving), the useris in a point call busy status; otherwise the user is in a point callfree status Group call talker group If a user is authorized touser-level transmission become a group talker, the user is in a groupcall talker status Group call received group If a user as a groupmonitor user-level received is receiving a service sent by a talker ofthe group, the user is in a group call received status Group start/endgroup After the group service is group-level start/end started, thegroup is in a start status, and when the group service is ended, thegroup returns back to the group end status again Group talker beingbusy/free If no member in the group group-level uplink busy (trigger ID,is authorized as a talker, trigger priority)/free the group talker isfree; if a member in the group is authorized as a talker, the grouptalker is busy, and it is required to notify other members of the groupof identity information and priority related information of the talker

In the embodiment of the present invention, the trunking call servicecontrol module manages the group status, and management for each statusshown in the above Table 1 is described separately below:

attached/detached: it is completed through a trunking UE registrationand deregistration process shown in the foregoing embodiment;

dedicated (busy/free): the trunking call service control module decideswhether to handle a point call initiation and end request, identifieswhether a UE performs a point call service; the LTE access networktransparently transmits a trunking application layer message such aspoint call initiation and point call end of a group UE and point callservice data based on the protocol stack A, and if the application layerinteraction is interrupted or timed out, the trunking call servicecontrol module may request, from the MME, status information of arelevant UE in the access network through the SGt interface to assistthe relevant UE in status management;

group transmission: the trunking call service control module decides agroup in which a UE is authorized with the group talker floor, and thetrunking call service control module may identify whether a UE is in agroup call talker status; the LTE access network transparently transmitstalker application and talker release of a trunking UE, and a groupapplication layer message such as talker floor grant based on theprotocol stack A;

group received: according to a current group service status, talkerstatus information, or active status feedback information of thetrunking UE, the trunking call service control module determines whetherthe trunking UE is in a group received status. If a trunking UE is notgranted as a talker UE of the group after a group service is initiated,the trunking UE is in the group received status by default; the trunkingUE may also be required to actively report, after receiving a groupservice initiation notification, to the trunking call service controlmodule through an application layer message that the trunking UE itselfhas accessed the group, thereby assisting the trunking call servicecontrol module in completing maintenance for the group received status;if the trunking UE actively exits the group service, the applicationlayer message may be sent based on the protocol stack A, to notify thetrunking call service control module that the trunking UE has exited thegroup, so that the trunking call service control module updates thestatus of the UE. Additionally, the trunking call service control modulemay also send a request to the MME through the SGt interface, so as toobtain a current monitoring UE status (ECM-IDLE/CONNECTED) of a group,and the MME may inform the trunking call service control module of arelevant UE status through the SGt interface;

group start/end: the trunking call service control module maintains theservice status of the group, and the LTE access network transparentlytransmits a trunking application layer message such as a group talkerstatus based on the protocol stack B;

uplink busy (trigger ID, trigger priority)/free: the trunking callservice control module maintains talker floor status management of thegroup, and the LTE access network transparently transmits a trunkingapplication layer message such as a group talker status based on theprotocol stack B, where after the trunking call service control moduleperforms the talker application response, talker authorization orrelease operation, the group talker status may be updated in the LTEaccess network; If no UE in the group is authorized as a talker UE, thegroup talker UE is free; if a UE in the group is authorized as a talkerUE, the group talker UE is busy, and identity information and priorityrelated information of the talker UE may be notified to other UEs of thegroup.

The group status update process is already described in the embodimentsin FIG. 6 (step 604 to step 604 c) and FIG. 7 (step 704 to step 704 c)above, and no more details are given here.

Corresponding to the embodiment of the trunking communication system andthe embodiment of the trunking communication method of the presentinvention, the present invention further provides an embodiment of atrunking management server and an embodiment of an access network, andfor specific implementation manners and functions of the embodiments ofthe trunking management server and the access network, reference can bemade to the description of the embodiments shown in FIG. 1 to FIG. 9.

Referring to FIG. 10, it is a block diagram of an embodiment of atrunking management server according to the present invention.

The trunking management server includes: a trunking call service controlmodule 1010 and a connected trunking call media gateway module 1020.

The trunking call media gateway module 1020 is configured to receiveservice data sent through the access network by a UE among trunking UEs,and forward the service data according to a communication type of theservice data, so as to implement user plane communication of thetrunking UE.

The trunking call service control module 1010 is configured to receive acommunication request sent through the access network by a UE among thetrunking UEs, and perform call control and bearer management on thetrunking UE according to a communication type of the communicationrequest, so as to implement control plane communication of the trunkingUE.

Specifically, the trunking call media gateway module 1020 can bespecifically configured to: when the communication type ispoint-to-point communication, forward service data, sent by a talker UEamong the trunking UEs, to a called UE among the trunking UEs throughthe access network; and when the communication type ispoint-to-multipoint communication, multicast service data, sent by atalker UE among the trunking UEs, to a monitoring UE among the trunkingUEs through the access network.

Specifically, the trunking call service control module 1010 can bespecifically configured to when the communication type is point-to-pointcommunication, send a unicast bearer establishment request or unicastbearer release request of a UE among the trunking UEs to the accessnetwork, so that the access network establishes an EPS bearer for theUE, or releases an established EPS bearer; and when the communicationtype is point-to-multipoint communication, send a trunking serviceinitiation request to the access network through the trunking call mediagateway module, so that the access network establishes a downlinkmulticast bearer for the trunking service according to the request, andallocates a resource to the trunking service.

Referring to FIG. 11, it is a block diagram of another embodiment of thetrunking management server of the present invention.

The trunking management server includes: a trunking call service controlmodule 1110, a connected trunking call media gateway module 1120, atrunking information management module 1130 and a trunking attributemanagement module 1140.

The trunking call media gateway module 1120 is configured to receiveservice data sent through the access network by a UE among trunking UEs,and forward the service data according to a communication type of theservice data, so as to implement user plane communication of thetrunking UE.

The trunking call service control module 1110 is configured to receive acommunication request sent through the access network by a UE among thetrunking UEs, and perform call control and bearer management on thetrunking UE according to a communication type of the communicationrequest, so as to implement control plane communication of the trunkingUE.

The trunking information management module 1130 is configured to managedefinition, storage and update of trunking UE information and trunkingsubscription information, where the subscription information includes agroup identifier, a group UE list, a trunking UE identity identifier,and a trunking UE priority definition.

The trunking attribute management module 1140 is configured to managedefinition, storage, and update of group attribute information, wherethe attribute information includes a group identifier, a group priority,a group area, and a group service type.

Specifically, the trunking call media gateway module 1120 may bespecifically configured to: when the communication type ispoint-to-point communication, forward service data, sent by a talker UEamong the trunking UEs, to a called UE among the trunking UEs throughthe access network; and when the communication type ispoint-to-multipoint communication, multicast service data, sent by atalker UE among the trunking UEs, to a monitoring UE among the trunkingUEs through the access network.

Specifically, the trunking call service control module 1110 may bespecifically configured to: when the communication type ispoint-to-point communication, send a unicast bearer establishmentrequest or unicast bearer release request of a UE among the trunking UEsto the access network, so that the access network establishes an EPSbearer for the UE, or releases an established EPS bearer; and when thecommunication type is point-to-multipoint communication, send a trunkingservice initiation request to the access network through the trunkingcall media gateway module, so that the access network establishes adownlink multicast bearer for the trunking service according to therequest, and allocates a resource to the trunking service.

Referring to FIG. 12, it is a block diagram of an embodiment of anaccess network according to the present invention.

The access network includes: an MME 1210, an access network gateway 1220and an eNodeB 1230 which communicate with each other. The access networkgateway 1220 includes a PDN gateway 1222 and an MEMS gateway 1221.

The access network gateway 1220 is configured to forward service data,sent by a trunking UE, to a trunking management server, so as toimplement user plane communication of the trunking UE.

The MME 1210 is configured to forward a communication request, sent by atrunking UE, to the trunking management server, so as to implementcontrol plane communication of the trunking UE.

Further, the access network gateway may specifically include (not shownin FIG. 12): a serving gateway communicating with the PDN gateway 1222,where each of the serving gateway and the MEMS gateway 1221 communicateswith the eNodeB 1230 and the MME 1210; the access network can furtherinclude: an MCE 1240 communicating with the MME 1210 and the eNodeB 1230separately.

Optionally, the PDN gateway 1220 is configured to: when user planecommunication of the trunking UE is implemented, and a communicationtype is point-to-point communication, receive service data sent by atalker UE among the trunking UEs, and send the service data to theserving gateway; the serving gateway is configured to forward theservice data to an eNodeB where a called UE among the trunking UEs islocated; the eNodeB is configured to send the service data to the calledUE; and the MBMS gateway is configured to: when user plane communicationof the trunking UE is implemented, and a communication type ispoint-to-multipoint communication, receive service data sent by a talkerUE among the trunking UEs, and send the service data to an eNodeB wherea monitoring UE among the trunking UEs is located; the eNodeB isconfigured to multicast the service data to the monitoring UE.

Optionally, the PDN gateway 1220 is configured to: when control planecommunication of the trunking UE is implemented, and the communicationtype is point-to-point communication, receive a unicast bearerestablishment request or unicast bearer release request sent by thetrunking UE, and establish an EPS bearer for the UE, or release anestablished EPS bearer.

The MBMS gateway 1210 is configured to: when control plane communicationof the trunking UE is implemented, and the communication type ispoint-to-multipoint communication, receive a trunking service initiationrequest of the trunking UE sent by the trunking management server, andsend the trunking service initiation request to the MME; the MME isconfigured to forward the trunking service initiation request to theMCE; the MCE is configured to establish a downlink multicast bearer fora trunking service of the trunking UE according to the trunking serviceinitiation request, and allocate a resource to the trunking service.

It can be seen from the foregoing embodiments that, the trunkingcommunication system in the embodiment of the present invention includesa trunking management server and an access network, the trunkingmanagement server includes a trunking call service control module and aconnected trunking call media gateway module, and the access networkincludes an MME, an access network gateway and an eNodeB whichcommunicate with each other, where the trunking call media gatewaymodule receives service data sent through the access network by atrunking UE, and forwards the service data according to a communicationtype of the service data, so as to implement user plane communication ofthe trunking UE; and the trunking call service control module receives acommunication request sent through the access network by a trunking UE,and performs call control and bearer management on the trunking UEaccording to a communication type of the communication request, so as toimplement control plane communication of the trunking UE. In theembodiments of the present invention, user plane communication andcontrol plane communication of the trunking UE may be implementedaccording to different communication types, so the trunking UE can bepaged in a multicast manner in a trunking communication procedure,thereby improving access performance and access efficiency of thesystem. Correspondingly, a downlink service can be sent in a multicastmanner, so occupancy on downlink channel resources in the system is alsoreduced.

Those skilled in the art can clearly understand that the technology inthe embodiments of the present invention may be implemented by hardwareonly or by software and a necessary universal hardware platform. Basedon such understandings, the technical solution in the embodiments of thepresent invention or the part that makes contributions to the prior artmay be essentially embodied in the form of a software product. Thesoftware product may be stored in a storage medium, which can be anROM/RAM, a magnetic disk, or an optical disk. The software productincludes a number of instructions that enable a computer device (apersonal computer, a server, or a network device) to execute the methodsprovided in the embodiments of the present invention.

The embodiments of the specification are described in a progressivemanner, reference may be made between the same and similar parts of theembodiments, and what is emphasized in the description of eachembodiment focuses on the part different from another part of otherembodiments. Especially, for the system embodiment, since the systemembodiment is basically similar to the method embodiment, thedescription is simple; for related parts, reference may be made torelated description of the method embodiment.

The above implementation manners of the present invention do notconstitute a limit to the protection scope of the present invention. Anymodification, equivalent replacement, and improvement made within thespirit and principle of the present invention should all fall within theprotection scope of the present invention.

What is claimed is:
 1. A trunking communication system, comprising: atrunking management server comprising a trunking call service controlmodule and a connected trunking call media gateway module; an accessnetwork comprising a mobile management entity (MME), an access networkgateway and a base station (eNodeB) which communicate with each other,the access network gateway comprising a multimedia broadcast multicastservice (MBMS) gateway and a public data network (PDN) gateway thatcommunicate with the trunking call media gateway module, wherein thetrunking call media gateway module communicates with the access networkgateway; wherein the trunking call media gateway module is configured toreceive service data sent through the access network by a first userequipment (UE) among at least one trunking UE, and forward the servicedata according to a communication type of the service data forimplementing user plane communication of the at least one trunking UE;and wherein the trunking call service control module is configured toreceive a communication request sent through the access network by asecond UE among the at least one trunking UE, and perform call controland bearer management on the at least one trunking UE according to acommunication type of the communication request for implementing controlplane communication of the at least one trunking UE.
 2. The systemaccording to claim 1, wherein: the trunking call service control moduledirectly communicates with the access network gateway; or the trunkingservice call control module communicates with the access network gatewaythrough the trunking call media gateway module.
 3. The system accordingto claim 1, wherein: the access network gateway further comprises: aserving gateway communicating with the PDN gateway, wherein each of theserving gateway and the MEMS gateway communicates with the eNodeB andthe MME; the access network further comprises: a multi-service customeredge (MCE) communicating with the MME and the eNodeB separately; and thetrunking management server further comprises: a trunking informationmanagement module and a trunking attribute management module thatcommunicate with the trunking call service control module separately. 4.The system according to claim 3, wherein: the trunking call servicecontrol module communicates with the MME through an SGt interface, orthe trunking call service control module communicates with the MBMSgateway through an SGmb interface; the trunking call media gatewaymodule communicates with the MEMS gateway through an SGmb-i interface;and the trunking call media gateway module communicates with the PDNgateway through an SGi interface.
 5. The system according to claim 3,wherein: the PDN gateway, the MEMS gateway and the serving gateway areintegrated in one network element; or the MME and the MCE are integratedin one network element; or the trunking attribute management module andthe trunking call service control module are integrated in one networkelement.
 6. The system according to claim 3, wherein: the trunking callmedia gateway module is configured to: when the communication type ispoint-to-point communication, send, to the PDN gateway, service datasent by a talker UE among the at least one trunking UE, wherein the PDNgateway forwards, through the serving gateway, the service data to aneNodeB where a called UE among the at least one trunking UE is located,so that the eNodeB sends the service data to the called UE; and when thecommunication type is point-to-multipoint communication, send, to theMEMS gateway, service data sent by a talker UE among the at least onetrunking UE, wherein the MEMS gateway sends the service data to aneNodeB where a monitoring UE among the at least one trunking UE islocated, so that the eNodeB multicasts the service data to themonitoring UE.
 7. The system according to claim 3, wherein: the trunkingservice control module is configured to: when the communication type ispoint-to-point communication, send a unicast bearer establishmentrequest or unicast bearer release request of a third UE among the atleast one trunking UE to the PDN gateway, so that the PDN gatewayestablishes an evolved packet system (EPS) bearer for the third UE, orreleases an established EPS bearer; and when the communication type ispoint-to-multipoint communication, send a initiation request for atrunking service of the at least one trunking UE to the MEMS gatewaythrough the trunking call media gateway module, wherein the MEMS gatewayforwards the request to the MCE through the MME, so that the MCEestablishes a downlink multicast bearer for the trunking serviceaccording to the request, and allocates a resource to the trunkingservice.
 8. The system according to claim 3, wherein: the trunkinginformation management module is configured to manage definition,storage and update of trunking UE information and trunking subscriptioninformation, wherein the subscription information comprises a groupidentifier, a group UE list, a trunking UE identity identifier, and atrunking UE priority definition; and the trunking attribute managementmodule is configured to manage definition, storage, and update of groupattribute information, wherein the attribute information comprises agroup identifier, a group priority, a group area, and a group servicetype.
 9. A trunking management server, comprising: a trunking callservice control module; a connected trunking call media gateway module;wherein the trunking call media gateway module is configured to receiveservice data sent through an access network by a first user equipment(UE) among at least one trunking UE, and forward the service dataaccording to a communication type of the service data for implementinguser plane communication of the at least one trunking UE; and whereinthe trunking call service control module is configured to receive acommunication request sent through the access network by a second UEamong the at least one trunking UE, and perform call control and bearermanagement on the at least one trunking UE according to a communicationtype of the communication request for implementing control planecommunication of the at least one trunking UE.
 10. The server accordingto claim 9, wherein: the trunking call media gateway module isconfigured to: when the communication type is point-to-pointcommunication, forward service data, sent by a talker UE among the atleast one trunking UE, to a called UE among the at least one trunking UEthrough the access network; and when the communication type ispoint-to-multipoint communication, multicast service data, sent by atalker UE among the at least one trunking UE, to a monitoring UE amongthe at least one trunking UE through the access network.
 11. The serveraccording to claim 9, wherein: the trunking call service control moduleis configured to: when the communication type is point-to-pointcommunication, send a unicast bearer establishment request or unicastbearer release request of a third UE among the at least one trunking UEto the access network for the access network establishing an evolvedpacket system (EPS) bearer for the third UE, or releasing an establishedEPS bearer; and when the communication type is point-to-multipointcommunication, send a initiation request for a trunking service to theaccess network through the trunking call media gateway module for theaccess network establishing a downlink multicast bearer for the trunkingservice, and allocating a resource to the trunking service.
 12. Theserver according to claim 9, further comprising: a trunking informationmanagement module and a trunking attribute management module which areconnected to the trunking call service control module separately;wherein the trunking information management module is configured tomanage definition, storage and update of trunking UE information andtrunking subscription information, wherein the subscription informationcomprises a group identifier, a group UE list, a trunking UE identityidentifier, and a trunking UE priority definition; and wherein thetrunking attribute management module is configured to manage definition,storage, and update of group attribute information, wherein theattribute information comprises a group identifier, a group priority, agroup area, and a group service type.
 13. An access network, comprising:a mobile management entity (MME); an access network gateway and a basestation (eNodeB) which communicate with each other, the access networkgateway comprising a public data network (PDN) gateway and a multimediabroadcast multicast service (MBMS) gateway; wherein the access networkgateway is configured to forward service data, sent by a first userequipment (UE) among at least one trunking UE, to a trunking managementserver for implementing user plane communication of the at least onetrunking UE; and wherein the MME is configured to forward acommunication request, sent by a second UE among the at least onetrunking UE, to the trunking management server for implementing controlplane communication of the at least one trunking UE.
 14. The accessnetwork according to claim 13, wherein: the access network gatewayfurther comprises a serving gateway communicating with the PDN gateway,and wherein each of the serving gateway and the MBMS gatewaycommunicates with the eNodeB and the MME; and the access network furthercomprises a multi-service customer edge (MCE) communicating with the MMEand the eNodeB separately; and
 15. The access network according to claim14, wherein: the PDN gateway is configured to: when user planecommunication of the at least one trunking UE is implemented, and acommunication type is point-to-point communication, receive service datasent by a talker UE among the at least one trunking UE, and send theservice data to the serving gateway; the serving gateway is configuredto forward the service data to the eNodeB where a called UE among the atleast one trunking UE is located; the eNodeB is configured to send theservice data to the called UE; and the MEMS gateway is configured to:when user plane communication of the at least one trunking UE isimplemented, and a communication type is point-to-multipointcommunication, receive service data sent by a talker UE among the atleast one trunking UE, and send the service data to an eNodeB where amonitoring UE among the at least one trunking UE is located; the eNodeBis configured to multicast the service data to the monitoring UE. 16.The access network according to claim 14, wherein: the PDN gateway isconfigured to: when control plane communication of the at least onetrunking UE is implemented, and the communication type is point-to-pointcommunication, receive a unicast bearer establishment request or unicastbearer release request sent by a third UE among the at least onetrunking UE, and establish an evolved packet system (EPS) bearer for theat least one trunking UE, or release an established EPS bearer; and theMEMS gateway is configured to: when control plane communication of theat least one trunking UE is implemented, and the communication type ispoint-to-multipoint communication, receive a initiation request for atrunking service of the at least one trunking UE sent by the trunkingmanagement server, and send the initiation request to the MME; the MMEis configured to forward the initiation request to the MCE; the MCE isconfigured to establish a downlink multicast bearer for the trunkingservice of the at least one trunking UE according to the initiationrequest, and allocate a resource to the trunking service.